﻿using System;

using System.Threading;

using System.Net.Sockets;
using System.Linq;
using System.Text;
using System.Net;
using System.Collections.Generic;

namespace GPSTrakingListenerTCPSerial
{

    // State object for reading client data asynchronously
    public class StateObject
    {
        // Client  socket.
        public Socket workSocket = null;
        // Size of receive buffer.
        public const int BufferSize = 1024;
        // Receive buffer.
        public byte[] buffer = new byte[BufferSize];
        // Received data string.
        public StringBuilder sb = new StringBuilder();
    }

    class Program
    {

        // Thread signal.
        public static ManualResetEvent allDone = new ManualResetEvent(false);

        static void Main(string[] args)
        {
            StartListening();
        }

        public static void StartListening()
        {
            // Data buffer for incoming data.
            byte[] bytes = new Byte[1024];

            // Establish the local endpoint for the socket.
            // The DNS name of the computer
            // running the listener is "host.contoso.com".
            //IPHostEntry ipHostInfo = Dns.Resolve(Dns.GetHostName());
            //IPAddress ipAddress = ipHostInfo.AddressList[0];
            IPAddress ipAddress = System.Net.IPAddress.Loopback;
            IPEndPoint localEndPoint = new IPEndPoint(IPAddress.Any, 8886);

            // Create a TCP/IP socket.
            Socket listener = new Socket(AddressFamily.InterNetwork,
                SocketType.Stream, ProtocolType.Tcp);

            // Bind the socket to the local endpoint and listen for incoming connections.
            try
            {
                listener.Bind(localEndPoint);
                listener.Listen(100);

                while (true)
                {
                    // Set the event to nonsignaled state.
                    allDone.Reset();

                    // Start an asynchronous socket to listen for connections.
                    Console.WriteLine("Waiting for a connection..." + DateTime.Now.ToLocalTime().ToString("hh:mm:ss.fff"));
                    listener.BeginAccept(
                        new AsyncCallback(AcceptCallback),
                        listener);

                    // Wait until a connection is made before continuing.
                    allDone.WaitOne();
                }

                Console.WriteLine("Finish ...");

            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }

            Console.WriteLine("\nPress ENTER to continue...");
            Console.Read();

        }

        public static void AcceptCallback(IAsyncResult ar)
        {
            // Signal the main thread to continue.
            allDone.Set();

            // Get the socket that handles the client request.
            Socket listener = (Socket)ar.AsyncState;
            Socket handler = listener.EndAccept(ar);

            // Create the state object.
            StateObject state = new StateObject();
            state.workSocket = handler;
            handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
                new AsyncCallback(ReadCallback), state);
        }

        public static void ReadCallback(IAsyncResult ar)
        {
            // Retrieve the state object and the handler socket
            // from the asynchronous state object.
            StateObject state = (StateObject)ar.AsyncState;
            Socket handler = state.workSocket;

            // Read data from the client socket. 
            int bytesRead = handler.EndReceive(ar);

            if (bytesRead > 0)
            {
                //if (ConvertToHexStringOne(state.buffer) == "0x80")
                if (state.buffer[2] == 0xB0 || state.buffer[2] == 0xB1)
                {
                    Console.WriteLine(ConvertToHexString(state.buffer, bytesRead));
                    // Not all data received. Get more.
                    handler.BeginReceive(state.buffer, 0, StateObject.BufferSize, 0,
                    new AsyncCallback(ReadCallback), state);
                }
                else
                {
                    Console.WriteLine(ConvertToHexString(state.buffer, bytesRead));

                    // Array.Resize<byte>(ref state.buffer, bytesRead);
                    Send(handler, state.buffer);
                }
                
               
            }                     
        }

        private static void Send(Socket handler, byte[] MessageByte)
        {
            byte[] byteData = new byte[] { 0x29, 0x29, 0x21, 0x00, 0x05 };
                byte[] byteCheckCode = new byte[] { 0x0D };
                ByteAppend<byte> byteAppend = new ByteAppend<byte>();
                byteAppend.Add(byteData);
                byteAppend.Add(new byte[] {MessageByte[MessageByte.Length-2], 0x80, 0x80});
                byteAppend.Add(new byte[] {CalcCheckCode(byteAppend.ToArray())});
                byteAppend.Add(byteCheckCode);

                byte[] byteMessage = byteAppend.ToArray();

                Console.WriteLine("Send:" + ConvertToHexString(byteMessage, 10));

                //string a = ConvertToHexStringOne(byteData1);
                //if ( a == "0x80")
                //{
                //    Console.WriteLine("Send:" + ConvertToHexString(byteData, 6));
                //    Send(handler, byteMessage);
                //}

            // Begin sending the data to the remote device.
            handler.BeginSend(byteMessage, 0, byteMessage.Length, 0,
                new AsyncCallback(SendCallback), handler);
        }

        private static void SendCallback(IAsyncResult ar)
        {
            try
            {
                // Retrieve the socket from the state object.
                Socket handler = (Socket)ar.AsyncState;

                // Complete sending the data to the remote device.
                int bytesSent = handler.EndSend(ar);
                Console.WriteLine("Sent {0} bytes to client.", bytesSent);

                handler.Shutdown(SocketShutdown.Both);
                handler.Close();

            }
            catch (Exception e)
            {
                Console.WriteLine(e.ToString());
            }
        }


        public static byte CalcCheckCode(byte[] MessageDevice)
        {
            byte num = 0;
            int num1 = 2;
            while (true)
            {
                bool length = num1 < (int)MessageDevice.Length - 2;
                if (!length)
                {
                    break;
                }
                num = (byte)(num ^ MessageDevice[num1]);
                num1++;
            }
            byte num2 = num;
            return num2;
        }

        public static string ConvertToHexString(byte[] MessageByte, int bytesRead)
        {
            Array.Resize<byte>(ref MessageByte, bytesRead);


            StringBuilder sb = new StringBuilder();
            foreach (byte b in MessageByte)
            {
                sb.AppendFormat("0x{0:X2},", b);
            }
            return sb.ToString();
        }


        public static string ConvertToHexStringOne(byte[] MessageByte)
        {
            return String.Format("0x{0:X2}", MessageByte[2]);
        }
    }
}
